This invention relates to information technology for reducing Internet traffic and latency, and more particularly, to delivery of Internet content to users via television channels.
Initially Web latency was blamed on so-called “slow last-mile”, i.e. connection to the Internet via dial-up phone modem and, as a result, cable and DSL modems have been developed for broadband access. However faster modems eliminate only one Internet bottleneck while grows of number of Internet users, popular portals and e-commerce create congestion beyond the “last mile”. Moreover, faster modems intensify Web surfing and encourage rich media on Web sites, and thus contribute to Internet traffic on servers and routers. First DSL and cable modem users may experience a relief but if most of Internet users go this way the long waiting time will be back. An efficient way for reducing Internet traffic is Web caching, i.e. storing frequently accessed Web pages closer to users instead of fetching them each time from original distant sites whenever the pages are requested. Web caching reduces the number of routers between users and content servers and thereby reduces but does not eliminate traffic.
Most of content stored on Web is created for promotion of products, services and ideas, and therefore targeted at an audience rather than a particular person. And while by its nature the content is intended for broadcast it is delivered individually to each user like mail and phone calls. A separate copy of requested Internet content is delivered to each user on the user's address even when many users are interested in the same content. That is how dial-up, cable and DSL modems work. Such a waste of computing and communication resources creates Internet traffic jams that users see as annoying delays in content delivery. Meanwhile there is no traffic on radio and television where all recipients of a particular content are tuned to the same channel and thus receive the same “copy” of content. So this is the best and apparently the only way to eliminate Internet traffic and latency: delivery of Internet content to users in a broadcast manner.
This invention is further development of a data broadcast technology for the Internet disclosed in U.S. Pat. No. 5,864,823 and three pending patent applications by the same applicant. The technology puts together interactivity of the Internet and the traffic-free feature of television.
The U.S. Pat. No. 5,864,823 discloses new data broadcast applications Commercial on Demand and Virtual Personal Store that allow advertisers to effectively use the most pertinent consumer data for promotion of their products and services without having actual access to the data. The patent also claims a broadcast distribution of entities of informational nature, such as books, newspapers, magazines, music, video and software via a broadcast medium (television) to recipients individually authorized via an addressable network (the Internet). The pending application Ser. No. 09/179,375 claims a data broadcast system for reducing Internet traffic and latency. In the system, Internet files are delivered via the Internet to a broadcast server located at a television center and then retransmitted in a broadcast manner to simultaneously reach an unlimited number of clients in the servicing area. The files are automatically downloaded in client computers at a time of their scheduled transmission and presented to users later any time on user's request. In the pending application Ser. No. 09/336,846 the technology is developed to support interactive Internet access via multiple one-way TV channels. A client computer sends a request to the broadcast server for a particular content via a two-way addressable link, such as telephone, the server downloads the content via the Internet, selects a channel for broadcast transmission of the requested content and send the number of the channel back to the client. The client tunes to the channel and downloads the content. If more than one client order the same content they receive it simultaneously from the same channel. The pending application Ser. No. 09/829,255 discloses a further improvement of the data broadcast technology minimizing a two-way addressable interaction between broadcast server and broadcast clients and combining interactivity of the Internet with the traffic-free feature of television in the most efficient way.
Along with elimination of traffic and latency, the data broadcast technology turns on green light for rich media as feasible Internet content. On the Internet, all files storing images, audio and video are compressed to save storage and make transmission faster. Generally, the more compression, the faster transfer and the worth picture. As soon as storage capacity and delays are not issues any more, the compression can be limited to a level where it does not sacrifice resolution. With the traffic-free Internet, broadband connection and huge storage in client computer, users can enjoy HD video, surround sound and photographic quality picture. The quality of presentation is very important for both entertainment and e-commerce.
The data broadcast technology contributes also to Internet security eliminating possibility of so-called denial-of-service (DOS) attack. Popular sites may experience thousands and even millions of hits daily, and when they get too busy, additional requests are rejected to avoid excessive delays. This is called “denial of service”. The DOS attack is a flood of artificially created traffic. The attack constitutes one of the greatest threats because victims have virtually no defense against it. The broadcast content delivery eliminates traffic no matter whether the traffic is natural or artificial and as a result, it eliminates a possibility of denial of service. Whatever is the flood of hits, only one copy of content is permanently transmitted over a TV channel so that every client could tune to the channel and download the copy.
With all those benefits the technology is supplemental rather than intrusive—it does not require any change in existent Internet infrastructure and standards. It is still user's choice how to access the Internet: via a dial up, a cable or a DSL modem, or via a broadcast client. However some Internet content intended for broadcast clients would be too “heavy” for the individual delivery via the modems. For example, it may take up to 7 hours to download a 1.5-hour movie over a cable modem.
At the same time, data broadcast creates a security problem: when information is distributed in a broadcast manner, everybody who has a receiver can be a recipient of that information. Meanwhile some content has to be protected against unauthorized reception because it is confidential or supposed to be paid. Encryption is the traditional way to secure a conditional (authorized) access but in such a widely open system as television it may happen to be not sufficient. In particular, cable TV providers complain that theft of service from scrambled premium and pay-per-view channels exceeds $5 billion annually. For that reason it is not a good idea for a telecommuter to access his company sensitive data over a cable modem even if the data is encrypted. Dial up and DSL modems are more secure because they deliver data over telephone, which is not a broadcast system. Lack of security may overweigh benefits of Internet access via a data broadcast network and therefore providing security in the network is an issue of paramount importance.
This invention presents a data broadcast network and a data broadcast protocol providing both open and conditional access to information transmitted over the network. The protection technique is originated in U.S. Pat. No. 5,280,497 by the same applicant. The patent discloses a protection of multichannel transmission based on a permanent pseudorandom redistribution of content channels among physical channels. The technique is an alternative or a supplement to encryption and, when combined with encryption, it creates a deadlock for attacker because neither of the two protections can be attacked before the other is defeated. In this application the technique is extended to packet-switching environment.